.stl won't slice properly

[markcowell23]

Not sure if this is where to put this, (just joined), but I need the answer urgently for school. I made a model in blender that I exported as an .stl file. Everything seemed to be going fine, until I sliced it. It didn't do anything; no error bestwashingmachine.in message, except the popup that it was successfully sliced. (Same result in both Slic3r and Printrun). Everything worked but there was nothing there anymore; if I did it in .obj, it was successfully previewed, but the same result when slicing. No error message, successfully sliced; nothing there. Please answer quickly, this is due in two days aaaah ;-; !!

facing same issue